MPharm Master of Pharmacy Medicinal Chemistry and Drug Design 2

Question 1

Which chemical modification is applied to convert a carboxylic acid to an ester prodrug to improve oral bioavailability?

Accepted Answer

Esterification

Answer

Esterification masks the carboxylic acid, increasing lipophilicity and membrane permeability; the ester is then hydrolyzed in vivo to release the active acid.

Question 2

In QSAR studies, which descriptor represents a drug's lipophilicity?

Accepted Answer

Log P

Answer

Log P (partition coefficient between octanol and water) is the standard QSAR descriptor quantifying lipophilicity of a drug molecule.

Question 3

Which type of interaction is primarily responsible for the binding of catecholamine drugs to beta-adrenergic receptors?

Accepted Answer

Ionic and hydrogen bonding interactions

Answer

Catecholamines interact with beta receptors through ionic interactions between the amine group and aspartate residues plus hydrogen bonds via the catechol hydroxyl groups.

Question 4

What is the significance of chirality in drug design as illustrated by thalidomide?

Accepted Answer

Different enantiomers can have drastically different pharmacological and toxicological effects

Answer

Thalidomide's R-enantiomer has sedative effects while the S-enantiomer is teratogenic, demonstrating that stereochemistry critically determines drug outcomes.

Question 5

Which property of a drug is described by the term 'metabolic stability'?

Accepted Answer

The rate at which a drug is metabolized by hepatic enzymes

Answer

Metabolic stability refers to how quickly hepatic enzymes (primarily CYP450s) transform a drug, influencing its half-life and bioavailability.

MPharm Master of Pharmacy Practice Test

MPharm Master of Pharmacy Practice Test

MPharm Master of Pharmacy Medicinal Chemistry and Drug Design 2